Trouble connecting to climate module

[nth]

I get this error when trying to run the example code listed in the climate module docs:

$ tessel run climate.js
TESSEL! Connected to TM-00-04-f0009a30-00514738-383c45c2.
INFO Bundling directory /Users/nick.heiner/tessel (~13.87 MB)
INFO Deploying bundle (16.53 MB)...
INFO Running script...
error connecting module { message: 'Cannot connect to Si7005. Got id: 0', type: 'Error', name: 'Error', stack: 'stack traceback:
	/app/node_modules/climate-si7005/index.js:90: in function 'next'
	/app/node_modules/climate-si7005/index.js:114: in function 'callback'
	builtin/tessel.js:637: in function <builtin/tessel.js:694>' }

This error actually occurs even if I disconnect the module entirely from my tessel, suggesting that even when I plug it in it's not actually connected correctly. Am I doing this wrong?

I have reproduced this with multiple tessels. I am not sure that this particular module has ever worked since I got it in the mail.

Thanks!
Nick

[nth]

I just noticed that the module says climate-si7020 on it but the docs say to install climate-se7005. I tried with climate-si7020 instead but it caused a different issue:

nick.heiner:~/tessel $ npm ls --depth=0
/Users/nick.heiner/tessel
├── climate-si7005@0.1.3
└── tessel@0.3.13

nick.heiner:~/tessel $ npm uninstall climate-si7005
unbuild climate-si7005@0.1.3
nick.heiner:~/tessel $ ni climate-si7020
npm http GET http://registry.npmjs.org/climate-si7020
npm http 304 http://registry.npmjs.org/climate-si7020
npm http GET http://registry.npmjs.org/climate-si7020/-/climate-si7020-0.1.0.tgz
npm http 200 http://registry.npmjs.org/climate-si7020/-/climate-si7020-0.1.0.tgz
climate-si7020@0.1.0 node_modules/climate-si7020
nick.heiner:~/tessel $ tessel run climate.js 
TESSEL! Connected to TM-00-04-f0009a30-00514738-383c45c2.
INFO Bundling directory /Users/nick.heiner/tessel (~13.87 MB)
INFO Deploying bundle (16.52 MB)...
INFO Running script...
Error: Could not find module "climate-si7005/index.js"
stack traceback:
	/app/climate.js:7: in function 'res'
	/_start.js:4: in function 'res'
	[T]: src/colony/lua/cli.lua:40: in function <[T]: src/colony/lua/cli.lua:39>

It's odd that index.js could not be found. It looks like it does exist in my node_modules:

nick.heiner:~/tessel $ ls node_modules/climate-si7020/
.npmignore      COPYRIGHT       LICENSE-APACHE  LICENSE-MIT     README.md       examples/       index.js        package.json    tests/

[nth]

Ok, so it does turn out that I'm a goober and I had it plugged into C when the code was looking for A. Oops. I've fixed that issue, and switched node_modules back to using the correct module, and now I'm getting a new error:

$ tessel run climate.js 
TESSEL! Connected to TM-00-04-f0009a30-00514738-383c45c2.
INFO Bundling directory /Users/nick.heiner/tessel (~13.87 MB)
INFO Deploying bundle (16.53 MB)...
{ [Error: LIBUSB_TRANSFER_TIMED_OUT] errno: 2 }

[jon]

Hey @nth,

Are you sure you're calling:

require('climate-si7020')

in your code? It seems like it's searching for climate-si7005/index.js still.

[kevin]

Check that nothing unnecessary is in the directory that's getting sent to Tessel. 16.53 MB is rather large, and it could be running out of memory.

You should use climate-si7020 since your module has si7020 printed on it (there are two hardware revisions of the climate module).

[nth]

@kevin, I saw that the script did require('tessel') so I concluded it would be necessary to have tessel in my node_modules, which is where that bulk comes from, but I guess that's not true? (I removed it without causing any problems haha.) Is tessel a magic module that you can require without having it in node_modules? Is require('tessel') run on the tessel itself different than what you get via npm install tessel?

@jon yep, that was the problem. I was using the wrong module. Thanks!

[nth]

I've submitted a PR that I think would avoid this issue in the future: https://github.com/tessel/climate-si7005/pull/22.

[Kelsey]

Pull request merged– thanks!

[kevin]

That's correct. The tessel package in NPM is the command line tessel tool that runs on the computer, and can also be used as a library to communicate with Tessels from Node on your computer. When you require('tessel') on the device, you get a different library that's built into the Tessel firmware that gives you access to the hardware IO.

It's kind of confusing and you're not the first to be tripped up by this...we should probably do something to make that more clear.

[jon]

We may want to change the tessel command line tool to be npm install tessel-cli. It doesn't have quite the same appeal as npm install tessel but it would probably be less confusing.

[nth]

Yes, I think that would be better. grunt has their cli in a grunt-cli, for instance.

Alternatively, you could leave that module name the same and change the one that's actually on the tessel. Personally, I think it's rather confusing that there's a magic thing you can require only on the tessel, that isn't related to your node_modules in the project you are deploying from. I think it would actually be less confusing to make that accessible through a global or do something like grunt:

module.exports = function(tessel) {
};

I know that globals are evil, but I feel that the magic around require('tessel') is violating the principle of least surprise.

[kevin]

@jon posted a proposal to rename require('tessel') to require('hardware') on the Tessel side.

Changing Tessel Hardware Export Name